From fd2c6e372b06ecda8d2464671b954a05abbee1ef Mon Sep 17 00:00:00 2001
From: Evgeniy Kulikov <kim@nspcc.ru>
Date: Sat, 22 Aug 2020 05:45:15 +0300
Subject: [PATCH] [#26] Implement DeleteMultipleObjects

closes #26

Signed-off-by: Evgeniy Kulikov <kim@nspcc.ru>
---
 api/handler/delete.go | 125 +++++++++++++++++++++++++++++++++++++++---
 1 file changed, 117 insertions(+), 8 deletions(-)

diff --git a/api/handler/delete.go b/api/handler/delete.go
index 11daaa8..2e70d94 100644
--- a/api/handler/delete.go
+++ b/api/handler/delete.go
@@ -1,13 +1,46 @@
 package handler
 
 import (
+	"encoding/xml"
 	"net/http"
 
 	"github.com/gorilla/mux"
 	"github.com/nspcc-dev/neofs-s3-gate/api"
 	"go.uber.org/zap"
+	"google.golang.org/grpc/status"
 )
 
+// DeleteObjectsRequest - xml carrying the object key names which needs to be deleted.
+type DeleteObjectsRequest struct {
+	// Element to enable quiet mode for the request
+	Quiet bool
+	// List of objects to be deleted
+	Objects []ObjectIdentifier `xml:"Object"`
+}
+
+// ObjectIdentifier carries key name for the object to delete.
+type ObjectIdentifier struct {
+	ObjectName string `xml:"Key"`
+}
+
+// DeleteError structure.
+type DeleteError struct {
+	Code    string
+	Message string
+	Key     string
+}
+
+// DeleteObjectsResponse container for multiple object deletes.
+type DeleteObjectsResponse struct {
+	XMLName xml.Name `xml:"http://s3.amazonaws.com/doc/2006-03-01/ DeleteResult" json:"-"`
+
+	// Collection of all deleted objects
+	DeletedObjects []ObjectIdentifier `xml:"Deleted,omitempty"`
+
+	// Collection of errors deleting certain objects.
+	Errors []DeleteError `xml:"Error,omitempty"`
+}
+
 func (h *handler) DeleteObjectHandler(w http.ResponseWriter, r *http.Request) {
 	var (
 		req = mux.Vars(r)
@@ -36,13 +69,89 @@ func (h *handler) DeleteObjectHandler(w http.ResponseWriter, r *http.Request) {
 }
 
 // DeleteMultipleObjectsHandler :
-//
-// CyberDuck doesn't use that method for multiple delete.
-// Open issue and describe how to test that method.
 func (h *handler) DeleteMultipleObjectsHandler(w http.ResponseWriter, r *http.Request) {
-	api.WriteErrorResponse(r.Context(), w, api.Error{
-		Code:           "XNeoFSUnimplemented",
-		Description:    "implement me " + mux.CurrentRoute(r).GetName(),
-		HTTPStatusCode: http.StatusNotImplemented,
-	}, r.URL)
+	var (
+		req = mux.Vars(r)
+		bkt = req["bucket"]
+		rid = api.GetRequestID(r.Context())
+	)
+
+	// Content-Md5 is requied should be set
+	// http://docs.aws.amazon.com/AmazonS3/latest/API/multiobjectdeleteapi.html
+	if _, ok := r.Header[api.ContentMD5]; !ok {
+		api.WriteErrorResponse(r.Context(), w, api.GetAPIError(api.ErrMissingContentMD5), r.URL)
+		return
+	}
+
+	// Content-Length is required and should be non-zero
+	// http://docs.aws.amazon.com/AmazonS3/latest/API/multiobjectdeleteapi.html
+	if r.ContentLength <= 0 {
+		api.WriteErrorResponse(r.Context(), w, api.GetAPIError(api.ErrMissingContentLength), r.URL)
+		return
+	}
+
+	// Unmarshal list of keys to be deleted.
+	requested := &DeleteObjectsRequest{}
+	if err := xml.NewDecoder(r.Body).Decode(requested); err != nil {
+		api.WriteErrorResponse(r.Context(), w, err, r.URL)
+		return
+	}
+
+	removed := make(map[string]struct{})
+	toRemove := make([]string, 0, len(requested.Objects))
+	for _, obj := range requested.Objects {
+		removed[obj.ObjectName] = struct{}{}
+		toRemove = append(toRemove, obj.ObjectName)
+	}
+
+	response := &DeleteObjectsResponse{
+		Errors:         make([]DeleteError, 0, len(toRemove)),
+		DeletedObjects: make([]ObjectIdentifier, 0, len(toRemove)),
+	}
+
+	if errs := h.obj.DeleteObjects(r.Context(), bkt, toRemove); errs != nil && !requested.Quiet {
+		h.log.Error("could not delete objects",
+			zap.String("request_id", rid),
+			zap.String("bucket_name", bkt),
+			zap.Strings("object_name", toRemove),
+			zap.Errors("errors", errs))
+
+		for _, e := range errs {
+			if err, ok := e.(*api.DeleteError); ok {
+				code := "BadRequest"
+				desc := err.Error()
+
+				if st, ok := status.FromError(err.Err); ok && st != nil {
+					desc = st.Message()
+					code = st.Code().String()
+				}
+
+				response.Errors = append(response.Errors, DeleteError{
+					Code:    code,
+					Message: desc,
+					Key:     err.Object,
+				})
+
+				delete(removed, err.Object)
+			}
+		}
+	}
+
+	for key := range removed {
+		response.DeletedObjects = append(response.DeletedObjects, ObjectIdentifier{ObjectName: key})
+	}
+
+	if err := api.EncodeToResponse(w, response); err != nil {
+		h.log.Error("could not write response",
+			zap.String("request_id", rid),
+			zap.String("bucket_name", bkt),
+			zap.Strings("object_name", toRemove),
+			zap.Error(err))
+
+		api.WriteErrorResponse(r.Context(), w, api.Error{
+			Code:           api.GetAPIError(api.ErrInternalError).Code,
+			Description:    err.Error(),
+			HTTPStatusCode: http.StatusInternalServerError,
+		}, r.URL)
+	}
 }